Shares in WPP (LON: WPP) plummeted over 22% on Thursday after reporting a fall in sales.

The advertising group reported a 1.5% fall in net sales for the third quarter when it was expected to reach a 0.3% growth.

Almost £3 billion was wiped off the group’s market value.

Mark Read, WPP’s new chief executive, said: “Clearly we have underperformed our competition in the third quarter.”

“We are not going to sugarcoat the reality,” he added.

WPP is struggling to perform following the departure of founder and former chief executive Sir Martin Sorrell in April.

Sorrell said when stepping down: “As I look ahead, I see that the current disruption we are experiencing is simply putting too much unnecessary pressure on the business.“

“That is why I have decided that in your interest, in the interest of our clients, in the interest of all shareowners, both big and small, and in the interest of all our other stakeholders, it is best for me to step aside.”

“As a founder, I can say that WPP is not just a matter of life or death, it was, is and will be more important than that. Good fortune and Godspeed to all of you … now Back to the Future.”

WPP has been struggling amid the growing competition from Facebook (NASDAQ: FB) and Google (NASDAQ: GOOG), whilst other big clients including Unilever (LON: ULVR) are spending less on advertising.

George Salmon, who is an equity analyst at Hargreaves Lansdown, said: “We’re yet to get the full details, but it looks like the over-riding theme of [Mark Read’s] restructure will be a simplification of the business. It’s easy to see why.”

“Taking over at a group where success depends so much on having an in-depth knowledge of all the various agencies and divisions was always going to be a serious challenge.”

“This journey has already started, and the decision to sell a stake in Kantar is the next step,” he added.

Shares in WPP are currently trading -16.88% (1112GMT).